Aerospace and military applications often provide unique challenges to design and manufacturing. The nature of these applications often requires limited run and small-lot productions that result in high cost because of the small quantity of individualized assemblies. Part cost can be extremely expensive due to the cost of tooling and long lead-time associated with developing and fabricating the tooling. By way of example, aerospace environmental control system ducts are commonly laid up using fiberglass lay-up techniques. Reliable and durable tooling is necessitated for this manufacturing technique. When multiple aircraft designs are implemented, then multiple specialized tools and lay-up procedures are also required. This quickly generates negative cost implications on part manufacturing.
Direct manufacturing has the ability to open the doors for short lead time, tool-less manufacturing of aerospace components. Existing applications, however, are frequently limited due to practical and existing size constraints on the build chamber or pool. The usable size on the build chambers commonly limits their application to relatively small-sized parts. Additionally, multi-part elements may require individual builds using direct manufacturing and thereby generate undue cost increases. The present invention seeks a unique methodology of harnessing the direct build methodology while overcoming limitations generated by the limited build chamber sizing. In addition, the present invention seeks a method for producing oversized direct manufacture elements while minimizing the required number of full height builds.
A concern when using direct manufacturing to produce large scale objects such as ducting arises as the desire for larger and lighter duct sections increases. As the duct sections become larger and lighter, the flexibility of the plastic material utilized in direct manufacturing may begin to lose the desired stiffness and rigidity necessary for proper operation. In addition, flow through these duct sections is often a significant factor in performance. It is often desirable to modify such flow to minimize, eliminate, divert, or improve airflow through the duct.
What is needed is a method for manufacturing oversized duct work using direct manufacturing that provided the desirable stiffness and rigidity to duct section. Additionally, it would be highly desirable to have a method of manufacturing such duct segments while simultaneously introducing elements suitable for tailoring the airflow through the duct section.